Research And Improvement Of OLSR Routing Protocol In Wireless MESH Network

The rapid development of wireless network technology has made it possible to allow users to access network and share resources anytime and anywhere.In recent years,wireless network infrastructure and performance are in a booming period,extensive researches and investigation reports lay the foundation for wireless network,and make it a hot topic in this field.The routing protocol is the core of network quality,good routing strategy can improve the performance of the network,now the majority of routing protocols are tailored for Ad hoc networks,there is not a consensus for wireless mesh network,so the problem of wireless mesh routing protocol has also been broad and deep researched,in recent years a lot of methods to improve the particularity wireless mesh architecture,protocol requirements are put forward aiming to enhance the wireless mesh network efficiency and robustness.This paper presents a new wireless mesh routing algorithm,MC-OLSR which is ameliorated by Optimized Link State Routing Protocol.In the analysis of wireless mesh architecture,the paper introduces its work mode and routing requirement.OLSR is adopted after analyzing fixed mode of the backbone network and the mobility of users,which need a good routing strategy.In OLSR,MPR set selection is the key part,but the mechanism is not fully applicable to the WMN,original MPR selection strategy has a longer interval for route updating and computation,meanwhile,link quality is not considered when computing route table,which often causes link congestion and lower network performance.To solve the problem,we use the maximal clique and weight to modify MPR set selection strategy,and improve the routing table,the algorithm select MPR nodes using the biggest bottleneck bandwidth to ensure the bandwidth utilization,meanwhile,it can follow the fair principles when covering nodes.Combining the original algorthim and the new concept to select small interference to compute MPR set,then modify HELLO message to confirm link quality by broadcasting and feedback.Finally,we can compute the MPR set by weight and maximal clique.This algorithm can not only improve network throughput but reduce packet loss rate,lower-end delay,it can also quickly respond to the complex network structure,improve network efficiency,avoid unnecessary data transmission delay and packet loss.This paper uses NS2 simulation platform to simulate routing protocol running in a wireless mesh network,the open source nature of NS2 make the improved protocol possible.Experiment was divided into three parts,the first experiment to simulate the three different protocols running on the same wireless mesh network topology,and conclude experimental analysis of network performance parameters for different protocols.Experiment 2 and 3 respectively simulate original OLSR protocol and MC-OLSR protocol in ideal and complex situations.Simulation results show,the OLSR protocol is more suitable for wireless mesh networks,the proposed MC-OLSR protocol under different scenarios have stable performance and reduces network latency and increase throughput,reduce data transmission of packet loss rate that comparing to OLSR.